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Thrombophlebitis

(Phlebitis · Blood Clot)

In this condition factsheet:

Thrombophlebitis is an inflammation of a vein due to a blood clot. The term comes from a combination of thrombus, meaning blood clot, and phlebitis, meaning inflammation or infection of a vein. When blood clots form, they release a number of toxic chemicals that cause inflammation of the vein.

Thrombophlebitis is classified as either superficial or deep. Deep thrombophlebitis is often called deep vein thrombosis (DVT). This condition is less common but more worrisome than superficial thrombophlebitis. Superficial thrombophlebitis is commonly seen in varicose veins and after insertion of intravenous (IV) tubes in the veins of the arms. Most cases of superficial thrombophlebitis resolve without any medical treatment.

Causes of Thrombophlebitis

A variety of things can cause inflammation of a superficial vein. One common cause is due to trauma or injury, for example, from IV catheters or some solutions and medications used in hospitals that pierce the vein wall and cause irritation. Any trauma to a vein (like a blow or injury from a car accident) will trigger a local inflammatory reaction that leads to pain, discomfort, redness, and swelling. During this process, there's an increased flow of blood to the injured area, and a blood clot often forms in the inflamed or injured area of the vein.

Formation of blood clots in the deep veins such as the legs or pelvis are often caused by inactivity following surgery, long distance air travel, stroke, or a major accident that causes people to be bedridden for long periods of time. Blood flow in the veins depends on contraction of surrounding muscles, so with extended bed rest, the blood starts to pool and blood clots can easily form.

Sometimes, thrombophlebitis is caused by a bacterial infection in the vein. The usual culprit is a bacteria called Staphylococcus, commonly found on the skin. Thrombophlebitis can also develop in the leg veins of pregnant women, in people with varicose veins, and in some people with cancer of the pancreas. People receiving cancer treatment can also be at risk for developing a DVT. Women over the age of 35 years who smoke and take oral contraceptives are at a higher risk of thrombophlebitis. People who have a pacemaker, a central line (a catheter that is place in a central vein), or are overweight may also be at risk. In certain cases, thrombophlebitis develops without any obvious reason.

Symptoms and Complications of Thrombophlebitis

Inflammation in superficial or surface veins, such as those used to insert IV lines in the arm or to draw blood, can produce pain, redness, swelling, warmth, and discomfort. Blood clots that form in superficial veins rarely break loose and travel in the blood to cause blockage (in places such as the lungs).

While many people with DVT have no signs or symptoms, the classic symptoms are:

firm swelling of the calf or leg

pain or tenderness

redness

increased local temperature (warmth)

dull, aching tightness in the calf, especially with walking

dilatation (widening) of the surface veins of the leg

shortness of breath (may be the first sign in some people)

DVT is often less painful than superficial thrombophlebitis but can lead to serious complications. The reason is that a blood clot that forms in deeper, larger veins (such as in the legs) can break free and become a traveling blood clot called an embolus. The embolus can travel and lodge in the lung; this condition is called a pulmonary embolism. This is a serious complication of DVT and occurs when the veins of the legs, arms, neck, abdomen, and pelvis are affected.

Because a deep vein clot may not cause symptoms early on, the first sign may be that the clot has broken loose and travelled to the lung. Symptoms of a pulmonary or lung embolus are breathlessness, fast heart rate (palpitations), rapid breathing (panting), chest pain, and coughing up blood. If you have any of these symptoms, you need to get emergency medical care right away.